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Kinematics of Deformation at the Southwest Corner of the Monument Uplift

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Kinematics of Deformation at the Southwest Corner of the Monument Uplift Kinematics of deformation at the southwest corner of the Monument uplift Item Type text; Thesis-Reproduction (electronic); maps Authors Kiven, Charles Wilkinson, 1949- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 30/09/2021 08:04:06 Link to Item http://hdl.handle.net/10150/555078 KINEMATICS OF DEFORMATION AT THE SOUTHWEST CORNER OF THE MONUMENT UPLIFT by Charles Wilkinson KLven A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 7 6 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of re­ quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg­ ment the proposed use of the material is in the interests of scholar­ ship. In all other instances, however, permission must be obtained from the author. SIGNED: ( hfiLWA APPROVAL BY THESIS DIRECTOR This the Lb has been approved on the date shown below: A/a</ Jo. G. H. DAVIS Date Associate Professor of Geosciences ACKNOWLEDGMENTS The idea for this study was conceived during the summer of 1974 while I was under contract with the Office of Arid Lands Studies and the Department of Geosciences, University of Arizona, to investigate the large-scale fold structures of the portion of the Colorado Plateau tec­ tonic province within the state of Arizona. That regional study was jointly funded by the National Aeronautics and Space Administration Grant No. NGL-03-002-313, the Arizona Oil and Gas Conservation Commission and the Department of Geosciences, University of Arizona. The air photos used for field mapping were obtained from the Arizona Highway Department. I would like to extend thanks to a number of diverse groups who probably do not know how they influenced the inception and outcome of this study. Some recognition must go to the Organization of Petroleum Exporting Countries whose oil embargo in late 1973 produced the need for the type of detailed exploration for potential petroleum reserves which helped to conceive this study. On a more personal level I would like to thank the people of the Navajo Nation, who kindly extended me permission to explore their varied and beautiful homeland. Mr. Martin link, Head of the Museum and Research Department of the Navajo Tribal Museum, was very helpful as a liaison be­ tween me and the Navajo Tribal Council and in keeping an eye out for me during the long summer of 1974• To Messrs. R. Terrence Sudden, Gene Suemnicht, and Thomas McGarvin, thank you for your unique discussions iii iv on not only academic matters, but also on such worldly subjects as huge tracts of real estate. Deepest gratitude is extended to all my friends who never could figure out what I was up to but who helped me through the rough times anyway. Above all others I am most thankful to Dr. George H. Davis, who was the source of the regional study from which this work sprang. His ideas, discussions, and creative criticisms were of incalculable value to me. But valued beyond his ability as a teacher is the bond of mutual respect and friendship which has grown during our association. TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS............................... vi HST OF TABLES .......................... ................. x ABSTRACT ......... xi INTRODUCTION.................................................. 1 Purpose of the S t u d y .................. HH CM Methods ........................................ Previous Workers .................. ........... <X\<0 Dynamic Models of the Origin of Monoclines . Relationship of Monoclines to Basement Structures Age of the Mbnqclinal Folding.............................. 10 STRUCTURAL G E O L O G Y ............ 12 Fol d s ................. 12 J o i n t s ................................................. 24 Faults .................................................... 30 DISCUSSION ............................................. 47 Introduction.............................................. 47 Basement Structures Associated with Uplifts ................ 48 Inferred Basement Structures in the Study Area ............ 51 Kinematics of Basement Block Movement...................... 55 Deformation in the Sedimentary R o c k s ............... 64 Kinematics of Distributed Shear ............... 70 CONCLUSIONS.................................................... 78 REFERENCES.................................................... 80 v LIST OF ILLUSTRATIONS Figure Page 1. Structure-Geologic Map of the Southwest Corner of the Monument Uplift ............................ in pocket 2. Structure Map of Folds in Phanerozoic Rocks, Colorado Plateau Tectonic Province of Arizona . in pocket 3* Schematic Diagram of a Monoclinal Fold Showing the Spatial and Geometric Relationships of the Limbs and Hinges ............ 13 4* Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Strata that Comprise the Lower Limb of the Organ Rock Monocline and the Upper limb of the Comb Ridge M o n o c l i n e ................ ••... 15 5. Photograph of the Organ Rock Monocline .................... 16 6. Lower-Hemisphere, Equal-Area r Pole-Density Diagram of Poles to Strata in the Middle and Upper limbs of the Organ Rock Mo n o c l i n e ............ 18 7* Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Strata in the Middle limb of the Cow Springs M o n o c l i n e ............. 20 8. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Strata in the Middle limb of the Comb Ridge Monocline.................................. 23 9. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Joints Collected in the Betatakin A r e a ............................. 26 10. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Joints Measured in Narrow Canyon in the Formations of the Glenn Canyon Group ........ 28 11. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Joints from the Middle limb of the Comb Ridge Monocline............. 29 vi vii LIST OF ILLUSTRATIONS— Continued Figure Page 12. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Joints from the Middle limb of the Organ Rock Monocline.................................. 31 13• Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Joints Measured in the Formations of the Glenn Canyon Group Exposed in the Middle limb of the Cow Springs Monocline.......... .............. 32 14* Discordant Faults Showing Minor Displacements.............. 33 15* Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Discordant Faults Measured in the Middle limb of the Comb Ridge Monocline .......... 35 16. Lower^Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Discordant Faults in the Middle limb of the Cow Springs Mo n o c l i n e .................... 36 17* Lower-Hemisphere Plot of Poles to Discordant Faults in the Organ Rock M o n o c l i n e ................... 37 18. Oblique-Slip Slickensides and Polish on Discordant Fault Surface in Middle limb of Organ Rock M o n o c l i n e ....................... 3$ 19. Chatter Marks and Slickensides on Large Block of Kayenta Sandstone from the Middle limb of the Comb Ridge Monocline .................................. 39 20. Sketch Showing Full Relationships of Cross-Fractures on Calcite-Bearing Discordant Fault in Kayenta F o r m a t i o n ............................................ 40 21. Cross-Fractures on Calcite-Bearing Discordant Fault in Kayenta Formation in Middle limb of Comb Ridge M o n o c l i n e ............................................ 40 22. Gouge-Bearing Concordant Fault in Aeolian Cross- Bedded Navajo Sandstone in the Middle limb of the Cow Springs Monocline ............................ 43 23. Slickensides on Concordant Fault Surface in the Navajo Sandstone in the Middle limb of the Comb Ridge Monocline ........................ 44 viii LIST OF ILLUSTRATIONS— Continued Figure Page 24. Lower-Hemisphere, Equal-Area, Pole-Density Diagram of Poles to Aeolian Cross-Bed Surfaces in the Navajo Sandstone from the Middle limb of the Comb Ridge Monocline ...... ............ ..... 45 25• Lower-Hemisphere, Equal-Area, Pole-DensityDiagram of Poles to Concordant Faults from the Navajo Sandstone from the Middle limb of the Comb Ridge M o n o c l i n e ....................... .................... 46 26. Schematic Cross-Section of Basement Structure....... 50 27. Reproduction of a Portion of the Residual Aeromagnetic Map of Arizona (Sauck and Sumner, 1971) .............. 52 28. Reproduction of the Residual Gravity Map of Arizona (West and Sumner, 1 9 7 3 ) ......... .................... 53 29. Structural Relief M a p ......................... ........... 56 30. Graph of the Change in Vertical Displacement Versus Angle of a Fau l t ...................................... 59 31• Block Diagram Showing Geometric
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